Intangible Assets, Net - Additional Information (Detail) - USD ($) $ in Millions				12 Months Ended
		Jun. 21, 2016		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Intangible Assets, Net (Excluding Goodwill) [Abstract]
Amortization expense related to finite-lived intangible assets				$ 50	$ 63	$ 66
Impairment of indefinite-lived or finite-lived intangible assets				0	0	$ 0
Acquired Indefinite-lived Intangible Assets [Line Items]
Goodwill		$ 3,268	[1]	15,066	11,825
Indefinite-lived Intangible Assets Acquired	[2]	16,137
Indefinite-lived Intangible Assets				26,957	11,009
Goodwill, Foreign Currency Translation Gain (Loss)				39
Franchise Rights [Member]
Acquired Indefinite-lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets		1,500		$ 0	$ 1,520
Visa Europe
Acquired Indefinite-lived Intangible Assets [Line Items]
Total purchase consideration		$ 18,784

[1] The excess of purchase consideration over net assets acquired was recorded as goodwill, which represents the value that is expected from increased scale and synergies as a result of the integration of both businesses.

[2] Intangible assets consist of customer relationships and reacquired rights, which have been valued as a single composite intangible asset as they are inextricably linked. These intangibles are considered indefinite-lived assets as the associated customer relationships have historically not experienced significant attrition, and the reacquired rights are based on the Framework Agreement, which has a perpetual term. Non-current assets and liabilities include deferred tax assets and liabilities that result in net deferred tax liabilities of $2.4 billion, which are primarily related to these indefinite-lived intangible assets, and are not expected to be realized in the foreseeable future.